An electrostatic capacitance is usually formed by glass of a funnel part of a CRT as dielectric material and inner and outer conductive coatings as electrodes. The panel part of the CRT is fastened tight by a metal band for safety, namely, against explosion of the glass bulb. When the CRT is used, both the metal band and the outer conductive coating should be grounded.
The outer conductive coating made of graphite is usually grounded by contacting a braided wire wound around the outer conductive coating with tension and grounding the braided wire.
The grounding braided wire is desirably long in the prior art. It is line contacted to the outer conductive coating with tension. A spring is desirable to pull the grounding braided wire with tension. This method is inferior in cost. Further, although the long grounding braided wire is easy to intertwine, it largely prevents automatic manufacturing in attaching it to the CRT.
To improve the above problem, a construction where the tension band (metal band) and the outer conductive coating are connected by an adhesive conductive tape is disclosed in Japanese Patent Laid-Open 3-102746.
In this case, the adhesive is unreliable over a long period. As for a CRT, the funnel part and the panel part are jointed by a seal and there is a danger of high tension leakage because the conductive tape directly touches the seal.